Sudden cardiac death refers to a phenomenon where a variety of heart diseases cause acute death in patients, with the most common causes being malignant arrhythmias such as ventricular tachycardia, ventricular fibrillation, or severe bradycardia, primarily related to myocardial infarction. However, not all cases of sudden cardiac death are due to myocardial infarction; this condition generally accounts for about 70%. Other causes of sudden cardiac death include existing dilated cardiomyopathy, thyrotoxic cardiomyopathy, or severe terminal stenosis of the mitral or aortic valves, which can also lead to sudden cardiac death. Another scenario involves atrial fibrillation leading to atrial thrombosis, causing thrombus detachment and resulting in extensive cerebral infarction leading to sudden death; this is also classified as sudden cardiac death. Therefore, while the majority of sudden cardiac deaths are related to myocardial infarction and arrhythmias, not all sudden cardiac deaths are due to myocardial infarction.